1. Field of the Invention
The present invention generally relates to safety devices for machines and more particularly to an improved machine having an automatic finger safety guard connected thereto.
2. Prior Art
Machinery which provides a work space accessible to the worker's fingers is frequently dangerous since a moving component of the machine operating on the work piece in the work space can damage the worker's fingers if they are intentionally or inadvertently inserted into the work space. One such type of machine is a resistance welding machine typically employing a vertically oriented fixed electrode mounted in a work space and a vertically oriented movable electrode spaced above and aligned with the fixed electrode. When the machine is turned on, the movable electrode descends toward the fixed electrode and contacts the work piece in the work space so that the welding operation can be carried out. The worker must be careful when the machine is on to keep his fingers out of the work space, otherwise they can be caught by the approximating electrodes and serious injury or amputation can occur.
Operation of such machinery characteristically causes some apprehension in the worker, reducing the speed with which the welding or other operation can be repeated upon successive work pieces. Many such machines incorporate no safety device at all. However, certain state and/or federal safety code standards now require safety guards and the like on certain of such machines. One conventional form of safety device installed on resistance type welding machines includes a pair of palm button switches which are activated by both hands of the welder in order to cause the movable electrode to approach the fixed electrode in the work space, so that welding can take place. However, since these palm switches effectively minimize the worker's hand activity, usually additional holding fixtures are required to permit proper positioning and manipulation of the work piece before, during and after the welding operation. Such holding fixtures are expensive to fabricate and install and in many cases reduce productivity.
Accordingly, it would be desirable to be able to provide a work machine having a finger accessible work space which could incorporate a finger safety guard which would not require supplemental holding and positioning devices for the work piece, would not reduce productivity and yet would provide ample safety for the worker. Such a guard should be inexpensive, easy to fabricate and install, durable and not subject to breakdown. The guard should not require the use of any additional hand movements of the worker.